Field of the Invention
The present invention relates to subtilase variants suitable for use in, e.g., cleaning or detergent compositions, such as laundry detergent compositions and dish wash compositions, including automatic dish wash compositions. The present invention also relates to isolated DNA sequences encoding the variants, expression vectors, host cells, and methods for producing and using the variants of the invention.
Description of the Related Art
In the detergent industry, enzymes have for many decades been implemented in washing formulations. Enzymes used in such formulations comprise amylases, cellulases, lipases, mannosidases, and proteases, as well as other enzymes or mixtures thereof. Commercially the most important enzymes are proteases.
An increasing number of commercially used proteases are protein engineered variants of naturally occurring wild type proteases Everlase®, Relase®, Ovozyme®, Polarzyme®, Liquanase®, Liquanase Ultra® and Kannase® (Novozymes A/S), Purafast®, Purafect OXP®, FN3® and FN4® (Genencor International, Inc.). Further, a number of protease variants are described in the art, such as WO 91/00345 (Novozymes A/S) and WO 94/23053 (Novozymes A/S) describes, e.g., mutations in position 262. The variants are suitable for use in, e.g., cleaning or detergent compositions.
A number of useful subtilase variants have been described many of which have provided improved activity, stability, and solubility in different detergents
However, various factors make further improvement of the proteases advantageous. The washing conditions such as temperature and pH changes over time and many stains are still difficult to completely remove under conventional washing conditions. Further, in wash conditions can result in inactivation of the enzymes (due to, e.g., pH, temperature or chelation instability) resulting in loss of wash performance during the wash cycle. Thus despite the intensive research in protease development there remains a need for new and improved proteases that have improved stability, in particular improved in wash stability and/or storage stability, and preferably similar or improved wash performance compared to the parent subtilase.